1. Work and simple machines:
Let’s try a quick “pre-assessment”
Work and simple machines:

2. Definition overview: Force: Work: Energy: Power: A Push or a Pull (N)
Work over a period of time
(watt)
Work:
Energy:
Ability to do work (calories)
Power:
Force applied x Distance
(Newton-meter)

3. Work is force done over a distance.
The formula is: W = F x d
-force is expressed in Newtons (N)
-distance is expressed in meters (m)
-Work is done in N-m… or Joules (J)

4. The work triangle looks like this:

5. Simple Machines
Ancient people invented simple machines that would help them overcome resistive forces and allow them to do the desired work against those forces.

6. Simple Machines The six simple machines are: Lever: 1st, 2nd, 3rd
Wheel and Axle
Pulley
Inclined Plane
Wedge
Screw
Write these down on your notesheet in the 8 boxes. There are 3 boxes for levers.

7. Simple Machines
A machine is a device that helps make work easier to perform by accomplishing one or more of the following functions:
changing the direction of a force,
increasing the magnitude of a force, or
increasing the distance or speed of a force.

8. Mechanical Advantage
It is useful to think about a machine in terms of the input force (the force you apply) and the output force (force which is applied to the task).
When a machine takes a small input force and increases the magnitude of the output force, a mechanical advantage has been produced.

9. Mechanical Advantage MA = output/input
Mechanical advantage is the ratio of output force divided by input force. If the output force is bigger than the input force, a machine has a mechanical advantage greater than one.
If a machine increases an input force of 10 pounds to an output force of 100 pounds, the machine has a mechanical advantage (MA) of 10.
In machines that increase distance instead of force, the MA is the ratio of the output distance and input distance.
MA = output/input

10. No machine can increase both the magnitude and the distance of a force at the same time.

11. The 6 Simple Machines Lever x 3 classes Screw Wedge Inclined Plane
Pulley
Wheel and Axle

12. First Class Lever
Fulcrum is between EF (effort) and RF (load) Effort moves farther than Resistance. Multiplies EF and changes its direction The mechanical advantage of a lever is the ratio of the length of the lever on the applied force side of the fulcrum to the length of the lever on the resistance force side of the fulcrum.

13. First Class Lever .
Common examples of first-class levers include crowbars, scissors, pliers, tin snips and seesaws.

14. Second Class Lever
RF (load) is between fulcrum and EF Effort moves farther than Resistance. Multiplies EF, but does not change its direction The mechanical advantage of a lever is the ratio of the distance from the applied force to the fulcrum to the distance from the resistance force to the fulcrum.

15. Second Class Lever
Examples of second-class levers include nut crackers, wheel barrows, doors, and bottle openers.

16. Third Class Lever
EF is between fulcrum and RF (load) Does not multiply force Resistance moves farther than Effort. Multiplies the distance the effort force travels The mechanical advantage of a lever is the ratio of the distance from the applied force to the fulcrum to the distance of the resistance force to the fulcrum

17. Third Class Lever
Examples of third-class levers can include tweezers, arm hammers, and shovels.
The bicep = 1st class

18. Inclined Plane

19. Inclined Plane
The Egyptians used simple machines to build the pyramids. One method was to build a very long incline out of dirt that rose upward to the top of the pyramid very gently. The blocks of stone were placed on large logs (another type of simple machine - the wheel and axle) and pushed slowly up the long, gentle inclined plane to the top of the pyramid.

20. Inclined Planes
An inclined plane is a flat surface that is higher on one end
Inclined planes make the work of moving things easier
A sloping surface, such as a ramp. An inclined plane can be used to alter the effort and distance involved in doing work, such as lifting loads. The trade-off is that an object must be moved a longer distance than if it was lifted straight up, but less force is needed. You can use this machine to move an object to a lower or higher place.  Inclined planes make the work of moving things easier.  You would need less energy and force to move objects with an inclined plane. 

21. Work input and output
Work input is the amount of work done on a machine.
Input force x input distance
Work output is the amount of work done by a machine.
Output force x output distance
Wout = Win
Fout x Dout = Fin x Din
10N x 3m = 2N x 15m
Din(E)
15 m
Dout(R)
3 m
Fin(E)
10 N

22. Inclined Plane - Mechanical Advantage
The mechanical advantage of an inclined plane is equal to the length of the slope divided by the height of the inclined plane.
While the inclined plane produces a mechanical advantage, it does so by increasing the distance through which the force must move.

23. Screw
The mechanical advantage of an screw can be calculated by dividing the circumference by the pitch of the screw.
Pitch equals 1/ number of turns per inch.

24. Pulleys Pulley are wheels and axles with a groove around the outside
A pulley needs a rope, chain or belt around the groove to make it do work

25. Diagrams of Pulleys Fixed pulley: Movable Pulley:
A fixed pulley changes the direction of a force; however, it does not create a mechanical advantage.
Movable Pulley:
The mechanical advantage of a moveable pulley is equal to the number of ropes that support the moveable pulley.

26. COMBINED PULLEY
The effort needed to lift the load is less than half the weight of the load.
The main disadvantage is it travels a very long distance. 

27. Wedges Two inclined planes joined back to back.
Wedges are used to split things.

28. Wedge – Mechanical Advantage
The mechanical advantage of a wedge can be found by dividing the length of either slope (S) by the thickness (T) of the big end. S
As an example, assume that the length of the slope is 10 inches and the thickness is 4 inches. The mechanical advantage is equal to 10/4 or 2 1/2. As with the inclined plane, the mechanical advantage gained by using a wedge requires a corresponding increase in distance. T

29. WHEEL AND AXEL
The axle is stuck rigidly to a large wheel. Fan blades are attached to the wheel. When the axel turns, the fan blades spin.

30. Wheel and Axel
The mechanical advantage of a wheel and axle is the ratio of the radius of the wheel to the radius of the axle.
In the wheel and axle illustrated above, the radius of the wheel is five times larger than the radius of the axle. Therefore, the mechanical advantage is 5:1 or 5.
The wheel and axle can also increase speed by applying the input force to the axle rather than a wheel. This increase is computed like mechanical advantage. This combination would increase the speed 5 times. 5 1

31. GEARS-Wheel and Axel
Each gear in a series reverses the direction of rotation of the previous gear. The smaller gear will always turn faster than the larger gear.

32. Formulas: IMA = DE DR AMA = FR FE OUTPUT = FR X DR INPUT = FE X DE
EFFICIENCY = OUTPUT = AMA
INPUT IMA

33. Note:
AMA – always less than IMA
OUTPUT – always less than INPUT

34. The next slides contain calculations you must know:
Lever:
All 3 classes
MA and Efficiency of AMA to IMA FE FR DR DE
FR x DR = FE x DE

35. Inclined Plane: What will the FE be? FR x DR = FE x DE
Mechanical advantage
Overall efficiency is based on IMA compared to AMA
FE = 10N
FR = 40N DE DR
What will the FE be?
FR x DR = FE x DE

36. Wheel and Axle What will the FE be? FR x DR = FE x DE MA or IMA
Efficiency of AMA to IMA
DE = 15cm
What will the FE be?
FR x DR = FE x DE
DR = 3cm
FR = 10N
FE = 2N

37. Wedge IMA:
How long divided by how fat/wide.

38. Pulley IMA Count the strings involved as the support.
Pulling down - count and subtract 1
Pulling up – count them all

39. Screw:
You do not have to calculate this one other than on your rube.

40. Videos:
Bill Nye ??

41. Ed-Heads:
You will complete all 5 of the given activities and send a screen shot word doc of each final score.

42. Rube Goldberg Machines
Rube Goldberg machines are examples of complex machines.
All complex machines are made up of combinations of simple machines.
Rube Goldberg machines are usually a complicated combination of simple machines.
By studying the components of Rube Goldberg machines, we learn more about simple machines

43. Safety Device for Walking on Icy Pavements
When you slip on ice, your foot kicks paddle (A),
lowering finger (B), snapping turtle (C) extends neck
to bite finger, opening ice tongs (D) and dropping pillow (E),
thus allowing you to fall on something soft.

44. Honda Commercial
Marble Fun Video

45. Squeeze Orange Juice Rube Goldberg Machine

46. Simple machine computer lesson/quest:
You must complete each section of the exercise:
-I need a screen shot of the “Find the Simple Machine”
-I need a screen shot of the
“Putting Simple Machines to Work” test
Simple machine computer lesson/quest: